Radius of Influence – groundwater pump well

Asked by: Widi Brady

What is the radius of influence of the pumping well?

In this work, the radius of influence of a pumping well is qualitatively defined as the maximum distance from the well up to which the influence of pumping is significant (Fig. 1a).

What is the radius of influence?

The “Radius of Influence” is defined as the maximum distance at which the drawdowns can be detected with the usual measure devices in the field [Dragoni, 1998]. Due to the use of numerical tools, the concept of “Radius of Influence” is nowadays of limited use [Dragoni, 1998].

What is specific capacity of well?

A well’s specific capacity equals the discharge rate (in gpm) divided by the water level drawdown (in feet). For example a well with a pumping rate of 200gpm with a 10foot drawdown has a specific capacity of 20gpm/ft of drawdown.

How do you calculate drawdown on a well?

Calculate the drawdown by subtracting the static level from the pumping level. saving well testing data. Also listed are some ways that you can use well drawdown measurements. Operating records should contain information about the static and pumping levels of a well, plus other important data.

What is zone of influence?

-The zone of influence is the area in which an activity or pressure could directly or indirectly impact part of the environment.

What is a well radius?

The radius is the distance from the well to a point where groundwater (and contaminant) travel time to the well is 2 years (or 5 years). Input data requirements are limited, consisting of the pumping rate, open (screened interval) of the well, porosity of the aquifer, and the selected TOT.

How do you calculate water well capacity?

Say our example well has a two foot diameter. We’d divide that by two, and get a one foot radius. Multiply that by pi, and then the height of nine feet, and you’ve got the well volume: Approximately 28.3 cubic feet.

Is 20 gpm good for a well?

You could have a great well water flow rate – say 20 gallons per minute – but if it the water will only run at that rate for five minutes before you run out, the well has a very poor water quantity (5 minutes x 20 gpm = 100 gallons of water) and it’s not a satisfactory well.

How do you measure the capacity of a well?

Turn on the well pump. Measure the flow rate as the time it takes to fill up the 5-gallon bucket. Discharge water at a rate of five gallons per minute for two hours (for a total of 600 gallons) or discharge water at a rate of four gallons per minute for four hours (for a total of 900 gallons).

How do you calculate the zone of influence?

The zone of influence extends out from the edge of the pipe trench twice the distance as the depth of the trench. (The ratio used is 2:1). For sand, filled ground (including controlled fill), loam, etc. the zone will extend twice the depth of the trench plus half the width of the trench.

What is a zone of influence in water?

Zone of Influence means the spatial area or volume of receiving water flow within which some degradation of water quality or use impairment is anticipated to occur as a result of a discharge.

What is zone of influence in construction?

Zone of influence is the volume of soil around the excavation affected by an external load (for example, vehicles, plant, excavated material). The influence of any loads near the excavation may cause ground collapse.

What is specific yield in geology?

Specific yield is the amount of water that is actually available for groundwater pumping, when sediments or rocks are drained due to lowering of the water table. Specific yield depends on the distribution of pores, their shape, and grain size.

What is well development?

Well development (or borehole development) of drilled wells is a part of normal well drilling procedure after the completion of the well and before the final disinfection. It is necessary to maximise the yield of the well and to optimise the filter capacity of the gravel pack after well construction (WAL 2010).

What is cone of depression in geology?

Cone of Depression



Pumping from a well in a water table aquifer lowers the water table near the well. This area is known as a cone of depression. The land area above a cone of depression is call the area of influence.

How is established recuperation tested?

Recuperation Test:



Total quantity of water percolated into the well is calculated by knowing cross-sectional area and rise in the water level after stoppage of pumping. The rate of percolation or the yield of well can be arrived at by dividing the quantity of water by the time.

What are the 4 types of aquifer?

Many different types of sediments and rocks can form aquifers, including gravel, sandstone, conglomerates, and fractured limestone.

How can I increase my well yield?

Depending on the findings, here are some of your options:

1. Drill Deeper. If your well is otherwise properly set up, drilling several feet deeper may improve the yield. …
2. Shock and Clean. …
3. Add a Storage Tank. …
4. Add a Secondary Well. …
5. Reduce Your Water Use.